jouslee

Hey guys, I'm not sure if this is a real problem or if it just happens. My brake fluid in my clutch master cylinder resevior is nearly black. I use the clear synthetic dot4 break fluid and did the clutch fluid flush by bleeding it maybe in May/June of 2006.

Thanks for your feedback!

Icemark

The four main types of brake fluid now available are DOT3, DOT4, DOT5 and DOT5.1. DOT3, DOT4 and DOT5.1 are glycol-based fluids, and DOT5 is silicon-based. The main difference is that DOT3, DOT4 and DOT5.1 absorb water, while DOT5 doesn't.

So when you say that you used a clear synthentic brake fluid... what did you use???

And dark DOT3, DOT4 or DOT 5.1 fluids means that it has absorbed a lot of water or you have bad/ breaking up seals in the master cyl.

Moisture enters the brake system in several ways. One of the more common ways is from using old or pre-opened fluid. Keep in mind that brake fluid draws in moisture from the surrounding air. Tightly sealing brake fluid bottles and not storing them for long periods of time will help keep moisture out.

jouslee

mm.. I used DOT3. Would it be safe to use DOT5 in my clutch master cylinder? or should i just use the standard DOT3?

Icemark

You can not use DOT5 without removing all the existing fluid, replace all the existing rubber seals and lines, then purging the system with isopropyl alcohol and then refilling with DOT5. You can not mix the two types (DOT3, DOT4, DOT5.1 vs DOT5) together.

And DOT3 is not a synthetic fluid.

jouslee

Alrighty Thanks alot!